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The numerical simulation results of the flow exhaust gases emitted by different aircraft engines are presented in this work. These results permitted the design of the most appropriate circular arc for a curved deflector to correctly direct the flow at the time planes are taking-off on the left runway number five of Mexico City International Airport (AICM) and not to affect the operability and route of the inter-terminal train, called as "Aerotren". This train has four carriages of 25 passengers each and transports users of Mexico City International Airport from terminal T-1 to terminal T-2 and vice versa. For the numerical simulation, several engine models of different aircraft were used, including the Boeing 747-400, the Boeing 777-200LR/-300ER, the Airbus A340-600, and the McDonnell Douglas MD11. The results presented here are those from the McDonnell Douglas MD11 airplane, which is the most critical case since it has an engine in the rear part of the fuselage on the vertical empennage, and this causes the flow of exhaust gases to arrive in a direction from top to bottom on the upper part of the Aerotren, which for safety should not exceed 15.0 m/s (54 km/hr). The impact of the explosion of these engine models was used to choose the most appropriate deflector curvature angle in the take-off area. The numerical simulation was carried out through the Fluent CFD program, solving the Navier-Stokes equations, the standard κ-ε model, turbulence, and atmospheric conditions in Mexico City. An experimental stage and the visualization of the behavior of the flow of exhaust gases within a wind tunnel are also presented. A 1: 125 scale model was used for both the deflectors with the radius of curvature obtained and the train car, in an area of one square meter and a grid background screen. [ABSTRACT FROM AUTHOR]

In this paper, we present the procedure of estimating the aerodynamic coefficients for a commercial aviation aircraft from geometric parameters at low-cruise-flight conditions using US DATCOM (United States Data Compendium) and XFLR software. The purpose of this research was to compare the stability parameters from both pieces of software to determine the efficacy of software solution for a wide-body aircraft at the stated flight conditions. During the initial phase of this project, the geometric parameters were acquired from established literature. In the next phase, stability and control coefficients of the aircraft were estimated using both pieces of software in parallel. Results obtained from both pieces of software were compared for any differences and the both pieces of software were validated with analytical correlations as presented in literature. The plots of various parameters with variations of the angle of attack or control surface deflection have also been obtained and presented. The differences between the software solutions and the analytical results can be associated with approximations of techniques used in software (the vortex lattice method is the background theory used in both DATCOM and XFLR). Additionally, from the results, it can be concluded that XFLR is more reliable than DATCOM for longitudinal, directional, and lateral stability/control coefficients. Analyses of a Boeing 747-200 (a wide-body commercial airliner) in DATCOM and XFLR for complete stability/control analysis including all modes in the longitudinal and lateral directions have been presented. DATCOM already has a sample analysis of a previous version of the Boeing 737; however, the Boeing 747-200 is much larger than the former, and complete analysis was, therefore, felt necessary to study its aerodynamics characteristics. Furthermore, in this research, it was concluded that XFLR is more reliable for various categories of aircraft alike in terms of general stability and control coefficients, and hence many aircraft can be dependably modeled and analyzed in this software. [ABSTRACT FROM AUTHOR]

The purpose of the article is to analyze the characteristics of aircraft, including aircraft of the Boeing and Airbus families, as well as to highlight the factors affecting the flight range depending on the dimension of the main aircraft. The possibilities of competition with Boeing and Airbus were considered and options for solving this problem were proposed. Formulas were used to identify the economic excellence of the aircraft and an analysis was made of the distribution of flights and major airports around the globe. A graphical model for the search for the rational appearance of the aerodynamic balancing scheme of long-range aircraft was presented. Among them were Boeing 747-400, Airbus A380-800 and VHI-5, the characteristics of which correspond to three specific zones of flight range. Conclusions were drawn about the dependence of the mass of the aircraft on the flight range, a scheme was determined according to which the dimension is the smallest, and a relationship was established between the duration of the flight and the fatigue of passengers and their impact on the requirements for comfort and ergonomics of a passenger seat depending on the duration of the flight. [ABSTRACT FROM AUTHOR]

Airline operators face accidental damages on their fleet of aircraft as part of operational practice. Individual occurrences are hard to predict; consequently, the approach towards repairing accidental damage is reactive in aircraft maintenance practice. However, by aggregating occurrence data and predicting future occurrence rates, it is possible to predict future long-term (strategic) demand for maintenance capacity. In this paper, a novel approach for integration of reliability modelling and inventory control is presented. Here, the concept of a base stock policy has been translated to the maintenance slot capacity problem to determine long-term cost-optimal capacity. Demand has been modelled using a superposed Non-homogeneous Poisson Process (NHPP). A case study has been performed on damage data from a fleet of Boeing 777 aircraft. The results prove the feasibility of adopting an integrated approach towards strategic capacity identification, using real-life data to predict future damage occurrence and associated maintenance slot requirements. [ABSTRACT FROM AUTHOR]

Abstract On March 8, 2014, a Malaysia Airlines Boeing 777 carrying flight MH-370 from Kuala Lumpur to Beijing disappeared during its flight. In this paper, we employ a model-based approach to capture and study the chain of events leading to the disappearance of the aircraft. We show that the critical reason for the aircraft's disappearance was a cyber-physical gap (CPG). The CPG is the difference between the real state of a physical entity and its state as perceived by cybernetic agents. Failure to acknowledge the CPG's existence, capture it in system models, and incorporate suitable mitigation mechanisms into systems exposed to CPG, has resulted in the past and may result in the future in severe consequences. In the MH-370 case, the plane's position and adherence to its flight course were misperceived by the air traffic control, resulting in failure to track and find the plane, to this day. Our approach to CPG analysis has been previously shown to assist both designers and users handle emergent situations resulting from CPGs, such as the Three-Mile Island nuclear reactor's partial meltdown accident in 1979. We propose several mitigation mechanisms, whose integration with air traffic control systems could help prevent similar cases in the future. [ABSTRACT FROM AUTHOR]

On 7 March 2014, a Boeing 777-200ER aircraft operated by Malaysian Airlines as MH370 on the route from Kuala Lumpur to Beijing abruptly ceased all communications and disappeared with 239 people aboard, leaving its fate a mystery. The subsequent analysis of so-called satellite "handshakes" supplemented by military radar tracking has suggested that the aircraft ended up in the southern Indian Ocean. The eventual recovery of a number of fragments washed ashore in several countries has confirmed its crash. A number of drift studies were undertaken to assist in locating the crash site, mostly focusing either on the spatial distribution of the debris washed ashore or on the efficacy of the aerial search operation. A recent biochemical analysis of the barnacles attached to the flaperon (the first fragment found in La Réunion) has indicated that their growth likely began in water of 24 °C; then the temperature dropped to 18 °C, and then it rose up again to 25 °C. An attempt was made in the present study to take into consideration all these aspects. The analysis was conducted by means of numerical screening of 40 hypothetical locations of the crash site along the so-called seventh arc. Obtained results indicate the likelihood of the crash site to be located between 25.5 and 30.5° S, with the segment from 28 to 30° S being the most promising. [ABSTRACT FROM AUTHOR]